我国华南扬子板块埃迪卡拉纪—寒武纪的含磷地层中产有丰富的呈现分裂特征的多细胞球状化石。由于有效信息的缺乏，长期以来，这些球状化石的生物属性及分类存在争议。我们在陕南寒武系宽川铺组获得的一些保存精美的分裂型球状化石，具有明显的多级四分体结构，通过与同层位产出的动物卵裂期胚胎化石、瓮安生物群中四分体结构的藻类化石对比，结果表明这些分裂球形化石很可能为多细胞藻类。

A large number of multicellular spherical microfossils occur in the phosphorus-bearing strata from the Ediacaran-Cambrian in South China,in which some of the large multicellular spherical fossils are characterized by cell cleavage. The affinity and classification of these spherical fossils have been controversial for a long time due to the lack of effective anatomical information.Here we report exceptional spherical and non-spherical fossils characterized by specific multi-level,tetrad cell structures from the Kuanchuanpu Formation in southern Shaanxi.These spherical fossils are likely akin to multicellular algae in comparison with cooccurred animal embryos in the cleavage stage and algal fossils with tetrad structures from the Ediacaran Weng’an biota in South China.

国家自然科学基金(Nos．：41472015，41672009，41621003，417720104002)；中央高校基金(No．310827171013)资助